Storage tanks are known in the art which are buried underground and which have inlets which extend up to the ground surface. These storage tanks are often used in automotive service stations and other environments. Often these storage tanks are emptied and refilled on a regular basis and it is advantageous that the inlets be clearly marked as to the contents of the storage tank they are associated with. For instance, it is highly undesirable for different types of fuels to be mixed together in the same storage tank. If inlets to the storage tanks are not clearly marked, it is possible that service station personnel or fuel delivery personnel would mistakenly put the wrong fluid into the storage tank. This is especially the case where multiple different storage tanks are located near each other such as in the service station environment.
Additionally, the ground above the storage tanks are often located in high vehicle traffic areas. Accordingly, any indicator plates must be capable of supporting vehicle loads and maintain their indicating ability even after repeated traffic has passed thereover. Indicia such as decals and paint have shown to be unreliable in the long term because repeated traffic loads and weather have abraded the indicia off of the indicator plates.
Thus, a need exists for an indicator plate which is durable enough to withstand traffic loads and yet maintain clearly an indicia correlative to the fluid within the associated storage tank.
The following prior art reflects the state of the art of which applicant is aware and is included herewith to discharge applicant's acknowledged duty to disclose relevant prior art. It is stipulated, however, that none of these references teach singly nor render obvious when considered in any conceivable combination the nexus of the instant invention as disclosed in greater detail hereinafter and as particularly claimed.
______________________________________ INVENTOR PATENT NO. ISSUE DATE ______________________________________ Neblett 3,134,184 May 26, 1964 Stitcha 3,936,207 February 3, 1976 Villard 4,907,361 March 13, 1990 Turner 5,056,454 October 15, 1991 ______________________________________
The patent to Turner teaches the use of an utility locator which is embedded in the ground and exhibits information about the character and location of utility facilities nearby. The invention of this application is distinguishable from Turner in that, inter alia, it is configured to withstand repeated vehicular traffic.
The remainder of the prior art listed above, but not particularly distinguished, diverge even more starkly from the present invention than the patent to Turner.